NGK Iridium IX Spark Plugs TR55IX (7164) 8-Pack — Iridium Tip, OEM-Grade Durability

NGK 7164 Iridium IX TR55IX spark plugs (8-pack) are high-durability, OEM-grade ignition plugs designed to deliver consistent spark performance and long service life for compatible engines.

These NGK Iridium IX spark plugs are commonly used as original-equipment replacements and engineered to balance reliable ignition, extended longevity and steady performance under everyday driving conditions. NGK is a global leader in spark plug manufacturing, and the TR55IX (part number 7164) brings a fine iridium-tipped center electrode and robust construction intended to meet factory specifications. Before ordering, verify fitment on NGK's application guide to confirm compatibility with your engine, drivetrain and required quantity.

Will these plugs fit my vehicle?

Compatibility depends on your vehicle's engine design and the manufacturer's recommended plug specifications. NGK maintains an online application database where you can look up the TR55IX (7164) by make, model and year to confirm fitment.

• Check NGK's official application tool for exact fitment details.
• Confirm required plug gap and torque specs in your service manual.
• This listing contains eight plugs—match quantity to your engine's cylinder count.

How do Iridium IX plugs affect performance and durability?

Iridium center electrodes are harder and finer than traditional alloys, producing a more concentrated spark and resisting wear longer. That typically translates to steadier combustion and extended service intervals under normal operating conditions.

• Fine iridium tip for focused, reliable spark.
• Durable construction reduces electrode erosion over time.
• Designed to match OEM ignition characteristics and keep emissions and drivability consistent.

What should I expect during installation and maintenance?

Installation follows standard spark plug procedures: verify gap, hand-start threads to avoid cross-threading, then torque to spec. Regular inspection and replacement intervals depend on driving conditions but are generally longer than conventional plugs due to the iridium electrode.

• Confirm factory gap if pre-gapped—adjust only if necessary.
• Use proper torque and anti-seize guidance from the vehicle manual.
• Replace in matched sets to maintain balanced ignition across cylinders.

Are these OEM-quality plugs worth the price?

NGK's reputation as the world's leading OEM spark plug supplier reflects consistent quality control and engineering, so many buyers find the Iridium IX series to be a cost-effective way to match factory performance while extending plug life. Value will depend on your vehicle and how long you expect between service intervals.

• Often specified as original equipment by manufacturers.
• Engineered for reliable starts and consistent combustion.
• Eight-plug packaging suits four-, six- and eight-cylinder engine applications where applicable.

Who is this for: The NGK 7164 Iridium IX TR55IX (8-pack) is suited for vehicle owners and technicians who want OEM-level replacement plugs with enhanced wear resistance and steady ignition performance. Choose these plugs if your vehicle's application list includes the TR55IX, you prefer long-life iridium electrodes, and you want a full set to service multiple cylinders at once. Always verify compatibility for your specific engine and follow manufacturer torque and gap specifications during installation.